Can not change the axis2c logger.

Can not change the axis2c logger because the macros AXIS2_LOG_DEBUG, AXIS2_LOG_INFO, etc calls directly to axutil_log_impl_log_debug, axutil_log_impl_log_info, etc and never calls to axutil_log_ops_t.write function pointer.
If the macros calls a generic function that calls the axutil_log_ops_t.write function pointer, everyone who wants to change the logger could create a new axutil_log_ops_t struct initializing it with your own pointers, like the XML parser, allocator, etc.